Your SlideShare is downloading. ×
ECG: Type II Second degree SA Block
Upcoming SlideShare
Loading in...5
×

Thanks for flagging this SlideShare!

Oops! An error has occurred.

×
Saving this for later? Get the SlideShare app to save on your phone or tablet. Read anywhere, anytime – even offline.
Text the download link to your phone
Standard text messaging rates apply

ECG: Type II Second degree SA Block

6,459

Published on

Published in: Health & Medicine
0 Comments
0 Likes
Statistics
Notes
  • Be the first to comment

  • Be the first to like this

No Downloads
Views
Total Views
6,459
On Slideshare
0
From Embeds
0
Number of Embeds
3
Actions
Shares
0
Downloads
63
Comments
0
Likes
0
Embeds 0
No embeds

Report content
Flagged as inappropriate Flag as inappropriate
Flag as inappropriate

Select your reason for flagging this presentation as inappropriate.

Cancel
No notes for slide

Transcript

  • 1. Prof.S.SUNDAR’s unit Dr.G.Rengaraj.PG ECG OF THE WEEK
  • 2. History & Exam.
    • A 58 yr. female came with
    • c/o chest pain – 1 hr
    • no h/o breathelessness, sweating, palpitations,syncope,leg swelling
    • Not a known DM/SHT
    • O/E pulse- 80/min, BP- 120/80
    • GC fair
    • CVS & RS – Normal
    • p/a – soft , CNS -NFND
  • 3.  
  • 4. Rhythm strip
  • 5.  
  • 6.
    • IN THIS ECG
    • Rate – 74/min
    • Rhythm - SINUS rhythm with absent P-QRS-T every 5 th wave
    • Axis- LAD
    • PR interval – 0.14 s
    • P, QRS & T wave morphology – Normal
    • The relatively short P-P intervals of 0.68 sec alternate with intervals of 1.36 sec – twice the cycle length of the shorter interval
  • 7. Ecg
    • This indicates that the long interval is due to the omission of a complete P-QRS-T complex
    • Every 5 th impulse is blocked at the SA junction resulting in 5:4 SA block
    • Type 2 second-degree SA exit block
  • 8. Sino-atrial block
    • The sinus impulse is blocked within the SA junction(between SA node–atrial myocardium)
    • A complete cardiac cycle ( P-QRS-T ) drops out
    • This is a form of exit block, since the impulse cannot exit from its pacemaker site
    • There are three types of SA block:
    • 1. First-degree
    • 2. second-degree- type 1(wenkebach)
    • type 2
    • 3. third-degree
  • 9. SA block
    • First-degree – the SA node impulse is merely slowed. It cannot be recognised on the ECG because SA nodal discharge is not recorded
    • Second-degree-
    • 1. type 1(wenkebach) – the P-R interval progressively lengthens, P-P interval progressively shortens prior to the pause, and the duration of the pause is less than two P-P cycles
    • 2.type 2 –no change in P-R interval before the pause, an interval without P waves that equals approx. two,three or four times the normal P-P cycle
    • Third-degree – complete absence of P waves . Difficult to diagnose without sinus node electrograms
  • 10. SA node disease
    • SA node dysfunction manifest in ECG as:
    • 1. sinus bradycardia
    • 2. sinus pauses
    • 3. sinus arrest
    • 4. sinus exit block
    • 5. chronotropic incompetence
  • 11. SA Node dysfunction
    • It can be classified as intrinsic or extrinsic
    • The distinction is important because extrinsic dysfunction is often reversible and should generally be corrected before considering pacemaker therapy
    • The most common causes of extrinsic SA node dysfunction are drugs & ANS influences that suppress automaticity and/or compromise conduction
    • Intrinsic sinus node dysfunction is degenerative and often characterised by fibrous replacement of the SA node or its connections to the atrium
  • 12. Extrinsic causes
    • Autonomic : carotid sinus hypersensitivity
    • vasovagal stimulation
    • Drugs : beta-blockers, CCB
    • digoxin
    • anti-arrhythmics( class 1 & 3)
    • lithium,amitryptiline
    • Hypothyroidism
    • Sleep apnea
    • Increased ICP
  • 13. Intrinsic
    • SSS
    • CAD ( chronic & acute MI )
    • Inflammatory – pericarditis
    • myocarditis
    • RHD
    • Senile amyloidosis
    • Chest trauma
    • Iatrogenic- radiation therapy
  • 14. Diagnosis
    • SA node dysfunction is most commonly a clinical or ECG diagnosis
    • Pacemaker implantation is the primary therapeutic intervention in pts with symptomatic SA node dysfuction
    • A number of drugs including Beta-blockers & CCB modulate SA node function and such agents should be discontinued prior to making diseases regarding the need for permanent pacing
  • 15. THANK YOU

×